Take a look at how the following document looks like embedded in a page:
Similar to YouTube, Scribd uses flash as base technology for rendering documents. Here's how the embedded code looks like:
<object width="500" height="200"><param name="allowScriptAccess" value="SameDomain" /><param name="movie" value="http://static.scribd.com/FlashPaperS3.swf?guid=g1t9xgitr71v6&document_id=28185&page=1" /><embed width="500" height="200" src="http://static.scribd.com/FlashPaperS3.swf?guid=g1t9xgitr71v6&document_id=28185&page=1" type="application/x-shockwave-flash"></embed> </object>
Getting the code is again as simple as YouTube: